1. Field of the Invention
The present invention relates to a shielding device, with which effective protection against intrusions of an integrated circuit can be achieved.
For integrated circuits in security-relevant applications, the difficulty arises that the circuits need to be protected against intrusions for spying on or analyzing the relevant circuit, e.g., by focused ion beam (FIB). Optical or mechanical analysis methods are also employed.
There are already a number of security concepts with which the integrated circuits can be protected against such intrusions, in particular, provided with a shield. An active shield, in which current-carrying conductor tracks and/or active components are used to shield against an external intrusion of the circuit, is particularly effective in this context. To date, the risk of the circuits being analyzed from the backside of the semiconductor chip, i.e., through the semiconductor substrate, has been ignored.
A so-called Silicon On Insulator (SOI) substrate is widely used in semiconductor technology. In terms of volume, it is, for the most part, a bulk silicon layer on which, separated from the bulk silicon layer by a thin insulator layer, there is a thin, generally crystalline body silicon layer in which the semiconductor components are formed.